Capt. Dave Mack of the Winnebago County Sheriff's Office said the sting involved an undercover officer posing as a prostitute. The men were responding to advertisements placed by police on Craigslist and Backpage.

"We're recognizing human trafficking in Wisconsin is becoming one of our major problems, so we're taking a very active role to combat it," Mack said.

It was the second sting the sheriff's office has done this year. The first netted six arrests. Several more stings are planned.